PVC or Pex residential fire sprinkler systems

[kyrbz]

The city is making me put in a fire sprinkler system in a commercially zoned property that I plan on living in. It's the lowest fire classification which allows me to use a residential pvc or pex system. I've think I've watched all the YouTube vids available on the topic. Just wondering if anyone on the forum has done one and has any words of wisdom about their experience installing/maintaining one. I have a 1.25" water line coming into the building with water pressure out the wazoo, so I think I'm good in that respect. It's a small single story living space (1000sqft) with an open floor plan, everything is still open and exposed, so it should be a relatively easy install at this point. The property was formerly a plumbing supply business with a small CMU structure that was the office which we are turning into the residence and another u-shaped warehouse (approx. 10,000sqft) that will be my shop and wife's studio. Fortunately the warehouse space does not have to have a fire sprinkler system, only the part we're turning into the residence.

 

[BrandonV]

Not sure if code permits but I'd make sure if you use PEX you have a pressure gauge after the pressure regulator. I get a little scared the regulator will fail, and you won't notice the pressure increase since the water isn't being used normally.

 

[Zeke]

Seems very odd to have a plastic fire system. I'd call the local fire dept if you have one. If not the city should have info on the requirements.
I see that PEX has a viable product for certain installations. the PVC approved is CPVC, a cousin with a higher temp rating.

Again, I'd get local advice.

 

[mike93lx]

There is an orange cpvc sold specifically for sprinkler system. Feels odd as I have always seen black iron, but for a small setup without risk of damage, it makes sense.

 

[kyrbz]

Seems very odd to have a plastic fire system. I'd call the local fire dept if you have one. If not the city should have info on the requirements.
I see that PEX has a viable product for certain installations. the PVC approved is CPVC, a cousin with a higher temp rating.

Again, I'd get local advice.

I'd agree that plastic seems odd for a fire sprinkler system, but PVC or Pex seems to be the standard for residential fire sprinkler systems with many municipalities now requiring them. I have an architect and engineer for the project. They were able to get the fire classification knocked down to the lowest rating which allows for the PVC/Pex residential system, so yes a PVC/Pex system has been approved by the city in my situation.

 

[kyrbz]

There is an orange cpvc sold specifically for sprinkler system. Feels odd as I have always seen black iron, but for a small setup without risk of damage, it makes sense.

The Pex system I'm looking at would be totally concealed including the sprinkler heads above the ceiling. The sprinkler heads are recessed in a can with a cover that pops off at around 150 degrees. One advantage of the residential systems is that only the sprinkler head above fire goes off in the event of a fire. The sprinkler head has a glass bulb filled with alcohol that explodes around 150 degrees and allows that individual sprinkler to spray.

 

[BrandonV]

I'd agree that plastic seems odd for a fire sprinkler system, but PVC or Pex seems to be the standard for residential fire sprinkler systems with many municipalities now requiring them. I have an architect and engineer for the project. They were able to get the fire classification knocked down to the lowest rating which allows for the PVC/Pex residential system, so yes a PVC/Pex system has been approved by the city in my situation.

PEX and CPVC are very popular for residential systems at least around me. The City of Scottsdale has required fire systems in residential constructions for decades now.

 

[BombShelter]

I haven't sold plumbing in 18 years so codes may have changed but the orange plastic was the material that met code back then.

 

[Youngandfree]

The Pex system I'm looking at would be totally concealed including the sprinkler heads above the ceiling. The sprinkler heads are recessed in a can with a cover that pops off at around 150 degrees. One advantage of the residential systems is that only the sprinkler head above fire goes off in the event of a fire. The sprinkler head has a glass bulb filled with alcohol that explodes around 150 degrees and allows that individual sprinkler to spray.

Most sprinkler heads are activated that way. Either temp sensitive glass or metal plug held in by a temp sensitive "solder" that melts and causes the plug to fall out.

 

[kyrbz]

Most sprinkler heads are activated that way. Either temp sensitive glass or metal plug held in by a temp sensitive "solder" that melts and causes the plug to fall out.

When you look at the companies that sell the residential systems, they make it sound like that's a unique feature to their system. I'm not that familiar with how the ********* pipe commercial systems work. There also seems to be a lot of banter back and forth between companies of why cpvc is better than pex or vice versa.

 

[NUTTSGT]

What does the code require ?

Is the installer required to be licensed ?

Sounds like a wet system you are installing, you're in the Midwest, how are you going keep it from freezing if you have an unheated attic space.

Unless you have a deluge system, only the head that is tripped, flows water..... don't believe what you see in movies or TV.

 

[GrayFlattop]

You probably need to have that installed by a licensed sprinkler fitter. If the AHJ doesn't require it, your insurance carrier likely will. Link

The good news is the CPVC systems go in quickly compared to black iron.

 

[kyrbz]

I'm leaning towards a pex system for this reason. I used to work in a shop that used schedule 80 pvc for the airlines. It was fine for many (10?) years and then one year, the solvent glued connections started to pop apart semi frequently. In my mind, a pex system would have fewer connections and maybe I trust a mechanical crimp over a glue connection?

 

[GrayFlattop]

PEX listed for fire sprinkler systems is available. Of course that would have the advantage of fewer connections.

Schedule 80 PVC for compressed air lines?!?!?!?! Of course it failed.

 

[kyrbz]

PEX listed for fire sprinkler systems is available. Of course that would have the advantage of fewer connections.

Schedule 80 PVC for compressed air lines?!?!?!?! Of course it failed.

That was done before I started working there. I would have strongly discouraged it if I had been there when they were putting it in. They ended up replacing it with a pex system. I'm not a big fan of compression fittings which is what the system they bought used. In the early days of the pex install, there were a lot of blow outs where the connections weren't seated perfectly.

 

[kyrbz]

What does the code require ?

Is the installer required to be licensed ?

Sounds like a wet system you are installing, you're in the Midwest, how are you going keep it from freezing if you have an unheated attic space.

Unless you have a deluge system, only the head that is tripped, flows water..... don't believe what you see in movies or TV.

You probably need to have that installed by a licensed sprinkler fitter. If the AHJ doesn't require it, your insurance carrier likely will. Link

The good news is the CPVC systems go in quickly compared to black iron.

I'm in the early stages of researching this topic, but what I've learned so far is that yes it has to be installed by a licensed sprinkler installer. My plumber who did the rough in on this project is not licensed to do sprinklers but he told me that he does know plumbers that are licensed to do the "residential sprinkler systems". The architect that stamped my plans told me that new cpvc residential sprinkler systems usually cost in the range of 10-15k. I think my situation is much simpler and smaller than the high end new construction houses they usually deal with, so I'm hoping for a much lower number.

Yes there are codes related flow/pressure and sprinkler head coverage etc.... Still researching that. If I have to hire a licensed installer, one would hope they know what meets code.

I do live in the midwest and the temperatures for the last 2 weeks have been brutal. The building I'll be installing this in has a flat pitched roof. No attic space. 4+ inch of new closed cell foam insulation sprayed in the ceiling. The finished ceiling inside will be a box rib corrugated metal panels. I'll be furring down the metal panels 1.5" below the bottom of the ceiling joist. I figured I'd run the pex in that 1.5" space. It's essentially inside below the insulation and just above the metal ceiling panels. I would hope that space wouldn't get that cold due to the insulation and heat from inside the house?

 

[mike93lx]

I'm leaning towards a pex system for this reason. I used to work in a shop that used schedule 80 pvc for the airlines. It was fine for many (10?) years and then one year, the solvent glued connections started to pop apart semi frequently. In my mind, a pex system would have fewer connections and maybe I trust a mechanical crimp over a glue connection?

Its great that it failed at the joints and not catastrophically.

If pvc is primed and glued properly, it will last for its designed purposed (water only) for a very long time. But nothing is perfect and plenty of pex had leaked as well

 

[dcg9381]

A friend built a house up near DFW, around 3000 sqft. Apparently anything over 3k required a "commercial" fire system. I'd never heard of that before.. By the looks of it, it's an iron pipe "full commercial" system.

I cannot think of anything worse to have in Texas (other than PVC) than a bunch of fairly wide diameter metal pipes full of water in our mininmal-R-value attics and semi-reliable power grid. Frustrating.

At least with a PEX system, it's not going to explode when frozen. Probably.

 

[mike93lx]

A friend built a house up near DFW, around 3000 sqft. Apparently anything over 3k required a "commercial" fire system. I'd never heard of that before.. By the looks of it, it's an iron pipe "full commercial" system.

I cannot think of anything worse to have in Texas (other than PVC) than a bunch of fairly wide diameter metal pipes full of water in our mininmal-R-value attics and semi-reliable power grid. Frustrating.

At least with a PEX system, it's not going to explode when frozen. Probably.

Are dry systems allowed?

 

[dcg9381]

Are dry systems allowed?

I don't know. Wouldn't those cost more? I saw the standard (iron?) pipe **** coming out of the ceiling which looks odd to me in residential.

 

[Sinatra]

You will want to or may be required by your insurance company to have the sprinkler system monitored. The sprinkler riser should be a branch off of your domestic water. Typically a valve tamper switch and a water flow switch are installed. If a head fuses, or the valve is inadvertently left closed, there is some indication at your home and notification sent. There should also be a testing schedule.

 

[cycle61]

Dry systems are definitely more complex. I've never priced them out, but virtually guaranteed they're more expensive.

 

[mike93lx]

I don't know. Wouldn't those cost more? I saw the standard (iron?) pipe **** coming out of the ceiling which looks odd to me in residential.

I'd expect. And if someone is going to under insulate, then the added cost is probably not something they would go for anyway.

Wet systems are regularly installed in places with temps that texas has never experienced

 

[dcg9381]

Wet systems are regularly installed in places with temps that texas has never experienced

The issue is that Texas is experiencing temperatures for periods of time that Texas has never experienced. On both the high and low ends.

People know how to build a house in Michigan for the cold. Texas, not so much. And it's costing billions (SWAG). We could argue that it's saved billions in costs that aren't necessary until they are. And I'll be honest, I've got a pipe that freezes somewhere between house and garage in the cold. I saw it going it, but didn't catch it. So now I heat the garage when it's below 20F.

But local energy recommendations for R values in residential are dynamic. I would like to see them being required as part of building code.. they are "loosely" required here.

 

[mike93lx]

The issue is that Texas is experiencing temperatures for periods of time that Texas has never experienced. On both the high and low ends.

People know how to build a house in Michigan for the cold. Texas, not so much. And it's costing billions (SWAG). We could argue that it's saved billions in costs that aren't necessary until they are. And I'll be honest, I've got a pipe that freezes somewhere between house and garage in the cold. I saw it going it, but didn't catch it. So now I heat the garage when it's below 20F.

But local energy recommendations for R values in residential are dynamic. I would like to see them being required as part of building code.. they are "loosely" required here.

Absolutely. I do understand that. Even here in VA, new construction has condensate lines for condensing furnaces in unconditioned attics. I spent Xmas eve 2022 at my buddy's 2 year old condo, in a single digit temp attic, thawing and replacing a frozen and cracked line. Thankfully no damage to the house, just a couple days without heat and a couple cold hours for us. It's dumb **** like that that wastes money and time

 

[Youngandfree]

When you look at the companies that sell the residential systems, they make it sound like that's a unique feature to their system. I'm not that familiar with how the ********* pipe commercial systems work. There also seems to be a lot of banter back and forth between companies of why cpvc is better than pex or vice versa.

Here's some decent info. As a longtime ago volunteer fireman, we carried sprinkler chocks to plug a sprinkler. Think wedge shaped block like a door stop that will slide into the frame of the sprinkler head and wedge into it to close it back off. May not be a bad idea to have one or two handy on the slim chance you need to shut one off.

5 Factors for Choosing the Right Fire Sprinkler

Take these five factors into account anytime that you are in search of a high quality fire sprinkler system.

www.chesapeakesprinkler.com

 

[Norcal]

The Pex system I'm looking at would be totally concealed including the sprinkler heads above the ceiling. The sprinkler heads are recessed in a can with a cover that pops off at around 150 degrees. One advantage of the residential systems is that only the sprinkler head above fire goes off in the event of a fire. The sprinkler head has a glass bulb filled with alcohol that explodes around 150 degrees and allows that individual sprinkler to spray.

All sprinklers are activated individually, all of them going off is Hollywood fiction.

 

[driftpin]

All sprinklers are activated individually, all of them going off is Hollywood fiction.

Different occupancies have different regulations. As NuttsGT mentioned, a deluge system has open heads, and yes, they all flow together on that branch once the water begins to flow. It's dry, until the sensing mechanism says to the fire pump, 'time to work.'

I used to be a plans examiner and inspector for PFP (private fire protection) systems, among other things (Florida Firesafety Inspector, and other certifications). Every part of a fire suppression system has to be a tested component rated for that type of use. Of course, that usually makes them more-expensive.

You cannot just throw-up what you believe is 'good-enough' for the system. It needs to be designed by a licensed person. As a point of interest, right now there are more psychiatrists than there are Fire Protection Engineers in the USA.

Yes to system monitoring, yes to periodic inspections by the AHJ. Depending upon the nature of what needs to be corrected, occupancy could be suspended in an extreme case, until the system is repaired and returned to service, and it passes inspection. The RPO (registered property owner) can do a sprinkler head replacement if a head has opened. Spare parts for the system are often kept where the system enters the occupancy, the fire code specifies how-many there should be. The prudent RPO will also have stoppers for the open sprinkler heads. The RPO can 'touch' the system, but repairs have to be done by licensed service providers and after that whatever inspections are necessary. See NFPA 13D for further information.

https://www.nfpa.org/ar/product/nfpa-13d-standard-for-the-installation-of-sprinkler-systems-in-one-and-two-family-dwellings-and-manufactured-homes/p0013dcode

 

[The Cobbler]

Yeah, I like the movies when the entire building is flooding with sprinklers on where there's no fire there.
reminds me of many years ago, a Saturday morning, one of the guys hit the sprinkler pipe with the forklift and snapped a coupling on a 6 or 8" line.
Yeah, there was black, stinky water everywhere LOL

 

[BrandonV]

Different occupancies have different regulations. As NuttsGT mentioned, a deluge system has open heads, and yes, they all flow together on that branch once the water begins to flow. It's dry, until the sensing mechanism says to the fire pump, 'time to work.'

I saw one of those in a library of all places... Library had a WHOLE section of sprinklers trigger by accident.

The irony? This is the science & engineering library... That $ is just the general contracting to get the building back to a normal state. It doesn't cover a fraction of the damages.

 

[NUTTSGT]

I saw one of those in a library of all places... Library had a WHOLE section of sprinklers trigger by accident.

The irony? This is the science & engineering library... That $ is just the general contracting to get the building back to a normal state. It doesn't cover a fraction of the damages.

This is why I wouldn't want a residential sprinkler system in my home. The water damage from the sprinkler system can be as bad or worse than the fire damage.

Those required to have residential sprinkler systems, does your insurance cover the water damage from activation or accidental activation ? Does it cover the water bill for water usage ?

 

[BrandonV]

This is why I wouldn't want a residential sprinkler system in my home. The water damage from the sprinkler system can be as bad or worse than the fire damage.

Those required to have residential sprinkler systems, does your insurance cover the water damage from activation or accidental activation ? Does it cover the water bill for water usage ?

Honestly you're run of the mill wet system is pretty dang reliable. I don't think sprinklers just pop wide open. I'd probably opt for a dry system if I could.

The deluge system at a library is just a head scratcher.

 

[NUTTSGT]

Honestly you're run of the mill wet system is pretty dang reliable. I don't think sprinklers just pop wide open. I'd probably opt for a dry system if I could.

The deluge system at a library is just a head scratcher.

I'm referring to frozen and broken.... You won't know till it warms up and thaws out.

Or the head pops like it's supposed to during a fire, you go from fire damage to water damage, both equally are destructive.

Question is worry about.... If you are required to have residential sprinklers, freezes, pops/splits linee and floods during thaw....will your insurance company try to weasel out of paying for damages because 1. Your don't have flood damage or 2. The freezing sprinkler line is an "act of God" ?

 

[BrandonV]

I'm referring to frozen and broken.... You won't know till it warms up and thaws out.

Or the head pops like it's supposed to during a fire, you go from fire damage to water damage, both equally are destructive.

Question is worry about.... If you are required to have residential sprinklers, freezes, pops/splits linee and floods during thaw....will your insurance company try to weasel out of paying for damages because 1. Your don't have flood damage or 2. The freezing sprinkler line is an "act of God" ?

Usually if a sprinkler pops during a fire the structure is probably a total loss without a sprinkler system.

No clue on the freezing. I suppose you could drain the system out on days your paranoid not that you should.

 

[NUTTSGT]

Usually if a sprinkler pops during a fire the structure is probably a total loss without a sprinkler system.

No clue on the freezing. I suppose you could drain the system out on days your paranoid not that you should.

Total loss on a residence, yes, maybe. Commercial probably not.

Drain your required by code sprinkler system and have a fire..... Ohhhh. Your insurance company will love you.

 

[BrandonV]

Drain your required by code sprinkler system and have a fire..... Ohhhh. Your insurance company will love you.

Good thing I'm in Arizona but yeah... Could be a bad day if you did that...

 

[NUTTSGT]

Good thing I'm in Arizona but yeah... Could be a bad day if you did that...

Ahhh. Az. You haven't had to deal with frozen sprinkler lines..... Come on to Ohio my friend.

 

[BrandonV]

Ahhh. Az. You haven't had to deal with frozen sprinkler lines..... Come on to Ohio my friend.

I would think a dry system or antifreeze mix would be required if there is a serious risk of a freeze.

Not sure if that stuff is doable on the residential side.

 

[BrandonV]

Looks like it boils down to making sure you have a good company engineer all these options in at the end of the day.

 

[NUTTSGT]

I would think a dry system or antifreeze mix would be required if there is a serious risk of a freeze.

Not sure if that stuff is doable on the residential side.

Most of them that have the plumbing in unheated areas use dry systems. However, those can issues if the air compressor dies or during a power outage.... Loss of air pressure. System trips and is full of water. If it's known any, cool, drain system. If it's not known about. ... you can have a whole system full of water freeze.